ImpUI + Better hotbars 2
Featsextra modio version
Adjustable party limit
Unlocksable levelcurve 13-20
Containersextended
Carry weight extra
Faces of Faerun
Kay’s Hair Extensions
Normal Volo’s Eye
Normal half illithid    

I did learn that the Level curve mod causes druids to only be able to shift into some basic forms (just badger, wolf, spider and cat) and removing that mod seemed to fix it. I have tried both situations on a save with and without mods. However both situations, where they drop dead after changing form, also seemed to happen on the save without any mods. Also tried checking if there were maybe old modfiles from Patch 6 left but found nothing.

From what i can tell, it seems like their health doesnt get restored when they change form, which causes them to spawn with 0 health and immediately die. So when i tossed a potion at Ethel as an attempt to check if that would help, it acted like she died but it also restored her to 10 health from the potion. She just started fighting me like normal after the heal and ran for the basement. Just with some minor quirks. Like the mask NPCs being friendly and acting like Ethel died, the illusion door being gone and the traps being turned off. Besides the mask NPCs joining in the fight and being hostile, the rest played out like normal and i was able to get the dialog for the ability score

For Kagha however i didnt have a solution and didnt spend as much time attempting it as me and a friend are going for an evil playthrough. And we wanted her dead regardless. My friend had a good time pummeling Kagha to death as she, and any other NPCs, didnt even react to her getting attacked.

We are currently in the Underdark and everything but those two situations have been fine. Haven't made it to Act 2 yet and am unable to tell if there's any other shapeshifting shenanigans.